Steerable Medical Device Having Multiple Curve Profiles

Abstract

A medical device, such as an introducer, includes a shaft having a lumen therethrough. A distal region of the shaft includes both a fixed curve region and a steerable region. According to certain aspects of the disclosure, the fixed curve region is more proximal than the steerable region. The fixed curvature of the distal region is selected to facilitate positioning of the distal end of the medical device in the general vicinity of a target, such as the left atrial appendage, while the steerable region allows for “fine tuning.” The lumen of the shaft is a large bore, typically on the order of about 12F to about 14F, to facilitate passage of larger medical devices, including left atrial appendage occlusion devices.

What is claimed is: 
     
         1 . A method of manufacturing an introducer, comprising:
 placing an inner liner over a mandrel;   placing a steering assembly over the inner liner, the steering assembly including a steering wire and a pull ring;   placing a braided wire reinforcing assembly over the inner liner;   placing an outer layer over the inner liner, the steering assembly, and the braided wire reinforcing assembly;   laminating the outer layer to the inner liner, thereby embedding the steering assembly and the braided wire reinforcing assembly within the outer layer; and   removing the mandrel, thereby forming a lumen,   wherein a portion of the introducer is formed into a fixed curvature.   
     
     
         2 . The method according to  claim 1 , wherein placing the braided wire reinforcing assembly over the inner liner comprises placing the braided wire reinforcing assembly over the inner liner and the steering assembly. 
     
     
         3 . The method according to  claim 1 , wherein the fixed curvature of the introducer is proximal of the pull ring. 
     
     
         4 . The method according to  claim 1 , further comprising placing a layer of a melt-processing polymer between a proximal section of the inner liner and a proximal section of the braided wire reinforcing assembly. 
     
     
         5 . The method according to  claim 4 , wherein the layer of a melt-processing polymer between the inner liner and the braided wire reinforcing assembly comprises a polyether block amide. 
     
     
         6 . The method according to  claim 1 , wherein the outer layer comprises a natural polyether block amide segment. 
     
     
         7 . The method according to  claim 1 , wherein a proximal end of the steering wire is pulled through an interstitial space in the braided wire reinforcing assembly, such that a first, more distal portion of the steering wire is radially inside the braided wire reinforcing assembly and a second, more proximal portion of the steering wire is radially outside the braided wire reinforcing assembly. 
     
     
         8 . The method according to  claim 1 , wherein the fixed curvature comprises a 45 degree curvature. 
     
     
         9 . The method according to  claim 1 , wherein the fixed curvature comprises a 115 degree curvature. 
     
     
         10 . The method according to  claim 1 , wherein the steering assembly is operable to deflect the introducer in a first plane, and wherein the fixed curvature bends the introducer in a second plane different from the first plane. 
     
     
         11 . A medical device, comprising:
 a shaft defining a lumen therethrough and having a distal region, wherein the distal region of the shaft includes a fixed curvature region and a steerable region; and   a steering assembly including a pull wire, the pull wire terminating in the steerable region of the shaft.   
     
     
         12 . The medical device according to  claim 11 , wherein the pull wire terminates in the distal region of the shaft distally of the fixed curvature, such that the steerable region is distal of the fixed curvature region. 
     
     
         13 . The medical device according to  claim 11 , further comprising a handle coupled to a proximal end of the shaft, wherein the handle includes an actuator coupled to the pull wire of the steering assembly. 
     
     
         14 . The medical device according to  claim 11 , wherein the steering assembly comprises a pull ring, and wherein the pull wire terminates at the pull ring. 
     
     
         15 . The medical device according to  claim 11 , wherein the shaft further comprises a braided wire reinforcing assembly, wherein the pull wire passes through an interstitial space in the braided wire reinforcing assembly such that a first, more distal portion of the pull wire is radially inside the braided wire reinforcing assembly and a second, more proximal portion of the pull wire is radially outside the braided wire reinforcing assembly. 
     
     
         16 . The medical device according to  claim 11 , wherein the shaft includes a proximal region, and wherein the proximal region comprises a segment of a natural polyether block amide positioned radially outside the braided wire assembly. 
     
     
         17 . The medical device according to  claim 11 , wherein the steerable region of the shaft is steerable in a first plane and wherein the fixed curvature region of the shaft curves in a second plane different from the first plane. 
     
     
         18 . A medical device, comprising:
 a lumenal shaft including a braided wire reinforcing layer and a distal region, wherein a first portion of the distal region is formed into a fixed curvature and a second portion of the distal region is deflectable; and   a handle coupled to a proximal end of the lumenal shaft.   
     
     
         19 . The medical device according to  claim 17 , wherein the first portion of the distal region is proximal of the second portion of the distal region. 
     
     
         20 . The medical device according to  claim 17 , wherein the fixed curvature is between 45 degrees and 115 degrees.